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1 <br />' During the early part of the pumping period, the cone of depression expanded while drawing down <br /> water in surrounding observation wells After approximately 60 minutes of extraction, the cone of <br /> depression, or the area of influence of the well, encountered a source of recharge which increased the <br /> vertical recharge in surrounding wells significantly <br />' Tune-drawdown from the constant-rate pumping test for the confined aquifer is plotted for both the <br /> pumping well and the observation wells As seen on the time-drawdown plots for observation wells <br /> MW-3, 4, 5, 7, 10, and pumping well MW 11, the first log cycle (1 0 to 10 0 minutes) was not used <br /> for any calculations The first set of calculations correspond to the second log cycle (10 0 to <br />' 100 0 minutes) of the extraction test The As values (drawdown, feet) corresponding to the log <br /> cycles were used in the calculations <br /> rTransmissivity and hydraulic conductivity values were calculated from the pumping well (MW-11) <br /> The transmissivity calculated from the second log cycle (10 0 to 100 0 minutes) was 960 gpd/foot <br /> r and from the third log cycle (100 0 to 1000 0 minutes) was 77 gpd/foot The estimated hydraulic <br /> conductivities for the second and third log cycles were 64 gpd/ft and 5 13 gpd/ft, respectively <br />' Data from four (4) observation wells (MW-3, MW-4, MW-7 and MW-10) were used to calculate <br /> transmissivity and the coefficient of storage for the aquifer at the Site Data obtained from an <br /> observation well is usually more accurate for transmissivity calculations The transmissivity and <br />' coefficient storage values from the second log cycle of monitoring well MW-3, located approximately <br /> 60 feet(east)from the extraction well were 352,000 gpd/ft and 0 205 respectively For the third log <br /> cycle the trarimussivity and coefficient of storage values were not calculated due to an increase in <br /> groundwater elevation <br />' For monitoring well MW-4, located approximately 70 feet downgradient of the pumping well, the <br /> transmissivity value calculated from the second tog cycle was 1,056,000 gpd/ft Coefficient storage <br /> for the second log cycle and transmissivity and coefficient of storage values for the third cycle were <br />' not calculated due to an increase in groundwater elevations <br /> For monitoring well MW-7, located approximately 95 feet downgradient of the pumping well, the <br />' transnussivity value calculated from the second log cycle was 105,600 gpd/ft Coefficient of storage <br /> for the second log cycle and transmissivity and coefficient of storage values for the third cycle were <br /> not calculated due to an increase in groundwater elevations <br /> rFor monitoring well MW-10, located approximately 60 feet upgradient of the pumping well, the <br /> transmissivity and coefficient of storage values calculated from the second log cycle were <br />' 11,733 gpd/ft and 0 0068, respectively Transmissivity and coefficient storage values for the third <br /> cycle were not calculated due to an increase in groundwater elevations <br /> r If an aquifer has a transmissivity of less than 1,000 gpd/ft, it can supply only enough water for <br /> domestic wells or other low-yield uses When transmissivity is 10,000 gpd/ft or more, well yields can <br /> be adequate for industrial, municipal, or lrngation purposes Average transmissivity values at the Site <br /> r <br /> A_1132$J1 ASA 13 <br /> 1 <br />